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"spread" and less depth. A well-cut stone is worth considerably more than a poorly cut one, even if the latter has a greater weight. Often in cutting a stone one-half and even more of its mass may be removed, and yet the stone be improved thereby. The brilliancy of a stone is increased, other things being equal, the larger the num­ber of facets which can be given it. The value of the stone must be taken into consideration in this connection, however. Stones of mod­erate value do not have their worth sufficiently increased by addition of numerous facets to warrant the expenditure of the extra time and labor that would be required to bring them to this condition. If a stone is strongly dichroic, as is iolite for example, the cutting must be in
such a direction as to bring out this quality in the highest degree. Similarly tourmaline, because of its dichroic properties, may make a dark and uninteresting stone if cut at right angles to the crystal-lographic axis, while if cut parallel to this axis it will make a bril­liant appearance and show two colors. Such stones as moonstone, labradorite, tiger's-eye, and others, which show chatoyancy only in certain directions, must obviously be cut with reference to this fea­ture. In transparent stones, the angle which the upper and lower facets make with each other should be a definite one, so as to reflect the light in the best possible manner.
Considering briefly and in order the forms of cutting above men­tioned, we may note first the brilliant. The brilliant cut is said to have been invented by Cardinal Mazarin in his endeavors to introduce the art of diamond-cutting into France. It is now the form most commonly given diamonds and is employed for many other transparent stones as well. As will be seen from the above figure, it is made up essentially of two truncated pyramids joined by their bases, the upper pyramid leaving one-third and the lower pyramid two-thirds of the length of the stone. The upper pyramid is called the crown, the lower the
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